crypto/asn1/a_bitstr.c

   1 /* crypto/asn1/a_bitstr.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58
  59 #include <stdio.h>
  60 #include "cryptlib.h"
  61 #include <openssl/asn1.h>
  62
  63 /* ASN1err(ASN1_F_ASN1_STRING_NEW,ASN1_R_STRING_TOO_SHORT);
  64  * ASN1err(ASN1_F_D2I_ASN1_BIT_STRING,ASN1_R_EXPECTING_A_BIT_STRING);
  65  */
  66
  67 int i2d_ASN1_BIT_STRING(ASN1_BIT_STRING *a, unsigned char **pp)
  68         {
  69         int ret,j,r,bits,len;
  70         unsigned char *p,*d;
  71
  72         if (a == NULL) return(0);
  73
  74         len=a->length;
  75
  76         if (len > 0)
  77                 {
  78                 if (a->flags & ASN1_STRING_FLAG_BITS_LEFT)
  79                         {
  80                         bits=(int)a->flags&0x07;
  81                         }
  82                 else
  83                         {
  84                         for ( ; len > 0; len--)
  85                                 {
  86                                 if (a->data[len-1]) break;
  87                                 }
  88                         j=a->data[len-1];
  89                         if      (j & 0x01) bits=0;
  90                         else if (j & 0x02) bits=1;
  91                         else if (j & 0x04) bits=2;
  92                         else if (j & 0x08) bits=3;
  93                         else if (j & 0x10) bits=4;
  94                         else if (j & 0x20) bits=5;
  95                         else if (j & 0x40) bits=6;
  96                         else if (j & 0x80) bits=7;
  97                         else bits=0; /* should not happen */
  98                         }
  99                 }
 100         else
 101                 bits=0;
 102         ret=1+len;
 103         r=ASN1_object_size(0,ret,V_ASN1_BIT_STRING);
 104         if (pp == NULL) return(r);
 105         p= *pp;
 106
 107         ASN1_put_object(&p,0,ret,V_ASN1_BIT_STRING,V_ASN1_UNIVERSAL);
 108         *(p++)=(unsigned char)bits;
 109         d=a->data;
 110         memcpy(p,d,len);
 111         p+=len;
 112         if (len > 0) p[-1]&=(0xff<<bits);
 113         *pp=p;
 114         return(r);
 115         }
 116
 117 ASN1_BIT_STRING *d2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a, unsigned char **pp,
 118              long length)
 119         {
 120         ASN1_BIT_STRING *ret=NULL;
 121         unsigned char *p,*s;
 122         long len;
 123         int inf,tag,xclass;
 124         int i;
 125
 126         if ((a == NULL) || ((*a) == NULL))
 127                 {
 128                 if ((ret=ASN1_BIT_STRING_new()) == NULL) return(NULL);
 129                 }
 130         else
 131                 ret=(*a);
 132
 133         p= *pp;
 134         inf=ASN1_get_object(&p,&len,&tag,&xclass,length);
 135         if (inf & 0x80)
 136                 {
 137                 i=ASN1_R_BAD_OBJECT_HEADER;
 138                 goto err;
 139                 }
 140
 141         if (tag != V_ASN1_BIT_STRING)
 142                 {
 143                 i=ASN1_R_EXPECTING_A_BIT_STRING;
 144                 goto err;
 145                 }
 146         if (len < 1) { i=ASN1_R_STRING_TOO_SHORT; goto err; }
 147
 148         i= *(p++);
 149         /* We do this to preserve the settings.  If we modify
 150          * the settings, via the _set_bit function, we will recalculate
 151          * on output */
 152         ret->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear */
 153         ret->flags|=(ASN1_STRING_FLAG_BITS_LEFT|(i&0x07)); /* set */
 154
 155         if (len-- > 1) /* using one because of the bits left byte */
 156                 {
 157                 s=(unsigned char *)Malloc((int)len);
 158                 if (s == NULL)
 159                         {
 160                         i=ERR_R_MALLOC_FAILURE;
 161                         goto err;
 162                         }
 163                 memcpy(s,p,(int)len);
 164                 s[len-1]&=(0xff<<i);
 165                 p+=len;
 166                 }
 167         else
 168                 s=NULL;
 169
 170         ret->length=(int)len;
 171         if (ret->data != NULL) Free((char *)ret->data);
 172         ret->data=s;
 173         ret->type=V_ASN1_BIT_STRING;
 174         if (a != NULL) (*a)=ret;
 175         *pp=p;
 176         return(ret);
 177 err:
 178         ASN1err(ASN1_F_D2I_ASN1_BIT_STRING,i);
 179         if ((ret != NULL) && ((a == NULL) || (*a != ret)))
 180                 ASN1_BIT_STRING_free(ret);
 181         return(NULL);
 182         }
 183
 184 /* These next 2 functions from Goetz Babin-Ebell <babinebell@trustcenter.de>
 185  */
 186 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value)
 187         {
 188         int w,v,iv;
 189         unsigned char *c;
 190
 191         w=n/8;
 192         v=1<<(7-(n&0x07));
 193         iv= ~v;
 194
 195         a->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear, set on write */
 196
 197         if (a == NULL) return(0);
 198         if ((a->length < (w+1)) || (a->data == NULL))
 199                 {
 200                 if (!value) return(1); /* Don't need to set */
 201                 if (a->data == NULL)
 202                         c=(unsigned char *)Malloc(w+1);
 203                 else
 204                         c=(unsigned char *)Realloc(a->data,w+1);
 205                 if (c == NULL) return(0);
 206                 a->data=c;
 207                 a->length=w+1;
 208                 c[w]=0;
 209                 }
 210         a->data[w]=((a->data[w])&iv)|v;
 211         while ((a->length > 0) && (a->data[a->length-1] == 0))
 212                 a->length--;
 213         return(1);
 214         }
 215
 216 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n)
 217         {
 218         int w,v;
 219
 220         w=n/8;
 221         v=1<<(7-(n&0x07));
 222         if ((a == NULL) || (a->length < (w+1)) || (a->data == NULL))
 223                 return(0);
 224         return((a->data[w]&v) != 0);
 225         }
 226